'92 vacuum pump

[ulhpilot]

Not a trick question: Where is the vacuum pump on a '92 MFI? When I get a definitive answer, I'll explain why I asked the question.

[DmaxMaverick]

It probably doesn't have one. Only a select few (such as Ca smog and some LD trucks) actually have/need it. If it does, it's belt driven, that's not the other usual belt driven accessories (PS pump, alternator, A/C, water pump).

[Robyn]

I agree with Maverick.

There would be no reason to have one on a 92

The Turbo (if equipped) was manually controlled with a Spring loaded unit.
The heater/HVAC system is all electronic (Except possibly some basic models that had cable controls)

The tranny is electronically controlled

No need for a vacuum pump.
***Exceptions****
As mentioned
Any smog items... EGR being the most common.

Starting in 1994 with the change to the electronic injection the vacuum pump was added to provide a means to control the turbo waste gate in a manner that allowed the ECM to "micro manage" the turbo boost pressure in concert with the fuel delivery.


We are curious to know the WHY ??????:D

[ulhpilot]

Thanks to Robyn and Maverick. The reason I asked is because, like you two, I couldn't think of why there would be a need for one.

But in searching for other parts online, just about every website shows a vacuum pump (belt driven) in the diagram for not only a '92 MFI but the '93 also. As far as I know, all '92 - '93 6.5s were turbo and HD F code, hence no smog stuff.

The only thing I can think of why the vacuum pump is listed is because the 6.2 NA was available these same years and sometimes the parts manufacturers assumed most parts were shared between the two engines. And to add to the confusion, when ordering a drive belt, you must specify no a/c or a/c, and vacuum pump or no vacuum pump.

I'm now waiting for someone with a '92 stating their engine has a vacuum pump :)